Tucking mechanism for wrapping machines



Sept. 23, 1952 v. P. HARVEY TUCKING MECHANISM FOR WRAPPING MACHINES 2SHEETSSHEET 1 Filed Aug. 21, 1947 P 1952 v. P. HARVEY 2,611,225

TUCKING MECHANISM FOR WRAPPING MACHINES Filed Aug. 21, 1947 2 saws-swam2 7 ZUM,M

Patented Sept. 23, 1952 MACHINES. Valentine" Pearce Harvey, London,England, assignorto MolinsMachine Company Limited,

London,=England; a British company Application August 21, 1947, swarm.769,801.. i In Great Britain August 2.6, 1M6 V This invention concernsimprovements in' or relating to wrapping or packingmachines andrefers-more particularly to machines ofthe kind in which the articles tobe-vvrapped or packed are moved by pushers on a continuousconveyorthrough wrapping mechanism. On such machines a wrapper is often foldedabout an article in such manner that parts thereof extend beyond theface of the article which is engaged by the pusher and usually, when thearticle is of rectangular block shape, the wrapper extends equally fromall four edges of the end'face. These extensionsare folded down on tosaid'face by folding opposite pairs in succession. For articles of thinrectangular blockshape such as cigarette packets there are two broadextensions and two narrow ones and it is usual to describe the foldingof the narrow ones as tucking and'this term 'will be used hereafter forconvenience It will be appreciated that the folding operations cannot beeffected or at {least completed unless the partly wrapped artieleismoved in advance of the pusher piece and this may be done by rollers asin Unitedstates patent specification I No. 1,517,307 or by movablelinkwork as in British patent specification No. 252,216 and thepresentinvention has for an object the provision of an improved device of thelatter class.

According to'the invention there is provided tucking mechanism formachines of the kind referred to comprising a pivoted tucker movablelaterally of the article path to effect the tucking operation andlengthwise of the path to remove the article from. the pusher'of theconveyor and means for operating the tucker so that its operative facelies at a comparatively large angle (e; g. 45) to the end face of thearticle at its first engagement with the wrapper and thereafter swingsduring its movement lengthwise of the path until it is substantiallyparallel with said end face. at first contact with the wrapper itengages with its extremity a portion of the wrapper which extends beyondthe article near to (e. g. at a distance not more than about one thirdof the thickness of the article from the end face of the article) and atthe end of the movement it is extreme precision and neatness and theresulting fold is smooth and taut. The tucker may be operated by a crankand connecting rod to execute the lengthwise movement while the lateralmove- The tucker may be so arranged that Thus the ment may be made by acam; 'Two camsyand followers maybe employed to avoid theuse of a springand secure positive and accurate motion of the tucker. A spring may beinterposed between the tucker and the cam mechanism as a safeguardto'prevent damage through accident thoughnormally the spring is notbrought into p y I The invention will be more particularly describedwith reference to the accompanying drawing in which: 4

Figure 1 is aplan of part ofa wrapping ma- .chine showing the mechanismfortucking one side of the wrapper;

" Figure '2 is an endelevation of-Figure =1;

7 Referring to the drawing, the articlel-Which *is in'this case acigarette carton and partly enclosed in "a transparent wrapper 2=ismoved along a path between side guides B'by' apusher piec'e'd. Thelatter is attached to a continuous conveyor in the well- -know'n mannerbut this is omitted from' -the' drawing for simplicitys" In'practice-theconveyor is usually anendless conveyor consisting of chains"running over "sprocket =whe'els at each endof the machine."

1 tucker 5 is fixed at the freeend or a lever B which ispivoted at -"lto a lever 8 which is jpivoted at 9 to a'cam lever i-Di Thecam -lever isprovided'with two followers 'or'rollers' 'H which engage cams l2 and I3which are rotatable" about an axis 14. Thus the movements of'thecamlever about its pivot 9 arepositive in both directions.

"The cam lever is operatively'coupl'ed to the. lever 8 throu'gh'a stiifspring 45 whicnem give should the tucker come --intol engagement:bypaccident with a -pusher; torexample in setting the 'machine or ifthe article jams by acciden'tLA lug 20 "on the lever Hl locates thelever 8 in position against the action of the spring 15. A connectingrod I6 is pivoted at H to the lever B and its other end is mounted on acrank pin l8 fixed on the cam l2. As the mechanism moves, the tuckerdescribes a path substantially as shown by the chain line and effectsthe tucking operation and thus the tucker follows the wrapper extensionas the latter bends about the corner of the carton face.

The tucker is also shown in an intermediate position in chain lines andactually in contact with the wrapper at the corner of the carton but acertain amount of latitude is allowed for in the engagement by makingthe cams adjustable about the axis I4. It is thought that the bestadjustment for the tucker is so to arrange it that at first contact withthe wrapper it engages with its extremity a portion of the wrapper ofthe machine and the opinion of the user. In

this intermediate position the tuckers have moved the article a shortdistance in advance of a the pusher as they move faster, asindicated'by' a long arrow, than the pusher which moves at a slower rateindicated by the short arrow and this diflerence in speed is maintaineduntil the pusher. is quite clear of the wrapper whereafter the pushercan move round the conveyor sprocket wheel and beneath the bed of themachine without disturbing the lower broad fold of the wrapper which canthen be folded down on to the article in any known manner. The guides 3may be slotted as shown in Figure 2, where they are-shown partly insection .on the line 2-2 of Figure l, and the tuckers 5 are in that caseforked so that the' article is controlled by the guideswhile tucking istaking place. Alternatively a narrower tucker, not forked, may beemployed in which case the guides .have a single slot to accommodate thetucker.

For simplicity, only one tucker is shown. in the drawing, but normallythere will be another similar tucker to operate on the other rear cor--ner of the packet. Both tuckers operate simultaneously and similarly.

It will be seen that by means of the present invention the tuckerengages at .an angle the face of the portion of the wrapper extendingbeyond the article, that is to say, it engages the wrapper somewherebetween the end of the article and the end of the extending portion.Thereafter the tucker swings, during its movement lengthwise of the pathof the article, about the corner of the end face of the article until itis substantially parallel with said end face. During this swingingmovement the tucker has a bodily translation inwardly whereby thewrapping material being folded by the tucker tends to be 'drawn aroundthe corner of the end face of the article, and in this way a neat endfold is provided. What I claim as my invention and desire to secure byLetters Patent is:

1. In a wrapping machine having conveyor means to move articles along astraight path during wrapping, tucking mechanism comprising incombination a tucking element having a surface for engaging and foldinga rearwardly extending part or a wrapper on an article being conveyed, asupport on which said element is pivoted for oscillating movement,independently of movement of said support, in a plane containing saidpath from an initial article engaging fposition, in.-which said surfaceforms an acute angle withsaid path, to a position substantiallyperpendicular to said path, means for oscillating said element to causesaid surface to move lengthwise of said path in the general direction oftraveler the articles, and to alter continuously the angular relation ofsaid surface to said path, and mechanism driven in timed relation tosaid means for so displacing said support toward and away from. saidpath that said element moves toward said path during pivotal movement of,.said element with said articles and while said surface is inengagement with the article wrapper, whereby the part of the wrapperbeing folded tends to be drawn around the corner of the end face of thearticle. I I I 2. Mechanism as claimed in claim 1, wherein the tuckingvelement is so arranged and timed relatively to the conveyor means thatthe wrapper-engaging surface. at its first contact with a wrapperengages with its extremity a portion of the wrapper which extends beyondthe article near to the end face of the article, and at the end of themovement is lying in contact with the said extending portion which isitself in contact with the end face.

3. Mechanism as claimed in claim 1, wherein the means to cause pivotalmovement of the tucking element comprises a crank and a connecting rodconnecting said crank to said element, and wherein the mechanism fordisplacing said support comprises a cam and a cooperating cam followercarried by said support.

4. Mechanism as claimed in claim 3, comprising a spring interposedbetween and operatively connecting said tucking element and said camlever to prevent damage. r

VALENTIN E PEARCE 1 REFERENCES CITED I The following references are ofrecord in the file of this patent:

UNITED STATES PATENTS I Date

